本論文的主要目的是應用拉凡格式法（Levenberg-Marquardt Method）結合套裝軟體 CFD-ACE+，探討自然對流條件下具有穿孔鰭片的LED徑向散熱模組的三維反算問題及其優化設計。一般工程問題通常透過正向計算求解已知條件下的物理量，這被稱為正算問題（Direct Problem）。而反向計算問題則是藉由已知的可測量或可計算資料推導出物理量，我們稱之為反算問題（Inverse Problem）。反算設計問題（Inverse Design Problem）同樣可以應用於最佳化設計，因為它利用希望的物理量對複雜的工程問題進行最佳化處理。
本研究主要探討了在固定體積和固定鰭片陣列數的條件下，通過在鰭片上進行穿孔的方式達到最佳散熱效果。此外，還通過紅外線熱像儀進行實際實驗，測量散熱鰭片表面的溫度分佈，以比較數值模擬結果與實際實驗的差異。
經過最佳化後，在散熱鰭片上穿孔確實能夠降低熱阻，發現靠近熱源的最底部孔洞設計較小，而最上方的孔洞設計則較大，孔洞大小的趨勢呈現由小到大的特點。在實驗驗證中，發現數值模擬結果與實際實驗之間的誤差非常小，這表明了最佳化設計的可靠性和準確性。這些結果進一步驗證了穿孔設計對散熱鰭片性能的重要影響，並確保了散熱鰭片在其工作環境下能夠更有效地散發熱量。

The main objective of this thesis is to utilize the Levenberg-Marquardt Method (LMM) in conjunction with the software package CFD-ACE+ to investigate the inverse problem and optimize the design of a three-dimensional LED radial heat dissipation module with perforated fins under natural convection conditions. This study primarily examines achieving optimal heat dissipation by perforating the fins while keeping the volume and fin array number fixed. Additionally, infrared thermography experiments are conducted to measure the temperature distribution on the surface of the heat dissipation fins. The aim is to compare the numerical simulation results with the actual experimental data.
After optimization, it was observed that perforations on the heat dissipation fins do indeed lead to a reduction in thermal resistance. It was found that the perforations near the heat source are designed smaller at the bottom, while those at the uppermost part are larger, indicating a trend of increasing hole sizes from bottom to top. During experimental validation, the disparity between numerical simulation results and actual experiments was found to be minimal, underscoring the reliability and accuracy of the optimized design. These findings further corroborate the significant impact of the perforation design on the performance of heat dissipation fins, ensuring their enhanced capability to efficiently dissipate heat in their operational environments.

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